Related Experiment Video
Updated: Jul 29, 2025
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
FeCl3-Catalyzed Decyanative [4 + 2] Annulation of α-Aminonitriles with Alkynes: Access to 2,4-Diaryl Quinolines in
Swetha Sathyendran1, Kesavan Muthu2, Karthick Govindan3
1Department of Chemistry, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Chengalpattu District, Tamil Nadu, India.
Abstract:
FeCl3-catalyzed decyanation of α-aminonitriles followed by a [4 + 2] annulation with terminal alkynes has been developed to synthesize 2,4-diaryl quinolines. A broad range of aniline, aldehyde, and arylacetylene derivatives were well tolerated to access 2,4-diaryl quinolines in moderate to good yields. The control experiment studies suggested that the reaction proceeds through a nonradical pathway involving Povarov-type [4 + 2] annulation from the in situ generated iminium species. The synthetic application of this strategy (i) includes gram-scale synthesis and (ii) a continuous-flow process for a few representative compounds in a shorter reaction time (22 min) and (iii) worked well with styrene as a proof of concept.
Related Concept Videos
Preparation of Alkynes: Dehydrohalogenation
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Preparation of Alkynes: Alkylation Reaction
Alkylation of terminal alkynes with primary alkyl halides in the presence of a strong base like sodium amide is one of the common methods for the synthesis of longer carbon-chain alkynes. For example, treatment of 1-propyne with sodium amide followed by reaction with ethyl bromide yields 2-pentyne.
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview

